Decanter centrifuge | Sludge dehydrator | Centrifugal dehydrator | mud dehydrator | Jinhua horizontal screw centrifuge | Complete set of sludge dewatering equipment

Application of coal mine wastewatersolid-liquid separation

2021-05-28 11:22:03

For a mine, the sewage pipe network and sewage treatment plant should be built in stages and batches according to the overall mine planning and drainage planning. It should be implemented in stages and gradually in place according to the goal of water environment protection.

(1) At present, some coal mine industrial sites and residential areas have built one sewage treatment plant respectively, two land acquisition, repeated construction, increased investment, high operation energy consumption, high management cost, scattered technical force and high cost of water treatment per ton. Generally speaking, the industrial site of the mine is not far away from the residential area, so it is more reasonable to build a sewage treatment plant of a certain scale together. It is considered to drain water from the residential area to the industrial site. If the pipeline is buried too deep, a sewage lifting pump station can be set in the middle, or a sewage treatment plant can be built in the middle of the industrial site and the residential area. Adopting the joint construction method can not only save investment, but also greatly reduce the operation cost.

(2) At present, in the design of many new mines, according to the norms and overall efficiency, the number of labor quota is small, but after the actual completion, the coal mine recruits a large number of labor personnel, and with the development of the coal mine, a large number of foreign personnel pour in, which increases the water consumption of the coal mine and the amount of sewage. Therefore, for the design of new coal mine sewage treatment plant, the retention coefficient should be considered in the construction scale.

(3) As the water quality and quantity of coal mine sewage vary greatly, reasonably determining the designed sewage quantity and quality is directly related to the investment, operation cost and cost-benefit of the project. Production sewage and domestic sewage shall be considered comprehensively, so as not to leave too much room to avoid increasing investment, leaving equipment idle or inefficient operation.

2、 Common process of coal mine sewage treatment design

Generally speaking, different coal mines have different requirements for effluent, so the treatment degree should be determined according to the requirements of China's environmental protection department to ensure the effluent quality. The quality of coal mine sewage is similar to that of general urban sewage, but different from urban sewage (urban sewage often includes some industrial wastewater). Its characteristics can be summarized as follows: large changes in water quality and quantity, low pollutant concentration, good biodegradability of sewage and low treatment difficulty.

In the design of coal mine sewage treatment plant, activated sludge process was adopted in the 1980s. Due to the low content of organic matter in sewage, microorganisms can not get the minimum nutrients during operation, so they can not form activated sludge and can not operate. The same problem also exists in the sewage treatment process of oxidation ditch. The return activated sludge cannot return, resulting in the original oxidation ditch system becoming a belt-shaped advection sedimentation tank with additional aeration, which can not meet the required treatment goal.

3、 Treatment of slime water by centrifugal separation

working principle:

The drum and the screw rotate at a high speed in the same direction with a certain differential speed. The materials are continuously introduced into the inner cylinder of the conveying screw from the feed pipe and enter the drum after acceleration. Under the action of centrifugal force field, heavier solid substances are deposited on the drum wall to form a sediment layer. The material conveying screw continuously pushes the deposited solid matter to the cone end of the drum and discharges it out of the machine through the slag discharge port. The lighter liquid phase forms an inner liquid ring, which continuously overflows the drum from the overflow port at the big end of the drum and is discharged out of the machine through the drain port. The machine can continuously feed, separate, wash and discharge materials under full speed operation. It has the characteristics of compact structure, continuous operation, stable operation, strong adaptability, large production capacity and convenient maintenance. It is suitable for separating suspensions with solid particle size greater than 0.005mm and concentration range of 2-40%.

Process features:

① Horizontal screw centrifuge uses the principle of centrifugal sedimentation to separate solid and liquid. Because there is no filter screen, it will not cause blockage.

② The centrifuge is suitable for thickening and dewatering all kinds of sludge.

③ In the dewatering process of centrifuge, when the feed concentration changes, the slip and torque of drum and screw will be automatically tracked and adjusted, so there is no need to assign special personnel to operate.

④ In the centrifuge, fine sludge can also be separated from water, so the dosage of flocculant is less. Generally, the dosage of mixed sludge during dehydration is 1.5kg/t [dry sludge], the sludge recovery rate is more than 95%, and the moisture content of sludge cake after dehydration is less than 40%.

⑤ The power consumption of each cubic meter of sludge dewatering of the centrifuge is 1kW / m3, and the noise during operation is less than 85dB. The centrifuge operates continuously for 24 hours a day. Except for shutdown, there is no need for cleaning water during operation.

⑥ The centrifuge occupies a small space and is easy to install and debug. The supporting equipment is only dosing and feed in and feed out conveyors. The whole machine is fully sealed and the workshop environment is good.

⑦ The vulnerable parts of the centrifuge are bearings and seals. The maintenance cycle of the unloading screw pusher is generally more than 3 years. The imported famous brand bearings and seals can ensure the long-term and high-intensity operation of the equipment, and the maintenance cycle can be greatly

extended after normal maintenance.

Description of special dehydrator for coal mine wastewater treatment:

The main machine is composed of column cone drum, screw unloader, differential system, bearing seat, frame, cover, main and auxiliary motors and electrical system. Under the action of strong centrifugal force generated by the high-speed rotation of the centrifuge, the coal mine wastewater is continuously dehydrated 24 hours a day. The main motor rotates the drum through the triangular belt, and generates the drum and spiral differential speed through the planetary gear differential and the auxiliary motor, so as to realize the functions of coal mine wastewater separation and pushing. The centrifuge has two automatic control functions, namely, differential speed control and torque control. Since the solid content of coal mine wastewater may fluctuate, the differential speed control system is adopted to ensure the stability of differential speed and constant mud dryness. The constant torque control is adopted to keep the centrifuge load in a stable state, so that the separation effect or the best state when used with flocculant, so as to ensure the reliable and safe operation of the centrifuge. The centrifuge has excellent sealing performance. The separation of coal mine wastewater works in a fully sealed state, making the environment clean.

"Special dehydrator for coal mine wastewater" series products have reasonable structure, advanced technology and fine production. They have great applicability for coal mine wastewater separation and obvious separation effect. It is specially suitable for coal slime wastewater treatment, iron ore wastewater treatment, Tunnel Cave slurry, tailings slurry treatment and other wastewater separation. The machine has the advantages of large treatment capacity, good separation performance, strong adaptability, low labor intensity, stable performance, convenient installation and operation, small floor area and low maintenance cost, and can realize closed continuous automatic separation, It truly embodies the advantages of "high efficiency, large displacement, energy conservation, balance, high temperature resistance and wear resistance". Through the practical use in the market in recent years, it has achieved good results and has been recognized by more and more customers.